Dual cure compositions, methods of curing thereof and articles therefrom

Abstract

The invention relates to a wind power plant comprising a vertically disposed shaft ( 2 ), a rotor with a number of straight or slightly curved blades ( 3, 4 ) which are parallel to the shaft ( 2 ); said rotor rotates round the shaft ( 2 ) whereby at least, one rotor blade ( 3, 4 ) which is disposed on the side facing the shaft ( 2 ) has a strip ( 5 ), which, in turn, is parallel to the shaft and projects from the surface of the rotor-blade ( 3, 4 ).

The invention claimed is: 
     
       1. A method of curing a dual cure composition comprising the steps of: (i) providing a dual cure composition comprising: at least one filler; at least one curable monomer comprising at least one of an ethylenic unit or cyclic ether unit or mixture thereof; at least one photoinitiator; and at least one thermal initiator; (ii) exposing the composition to radiation of a wavelength from a radiation source for a time to at least partially photocure the composition and to provide an exotherm sufficient to continue curing of the composition by thermal curing upon terminating exposure of the composition to the radiation to form a cured composition wherein the filler comprises carbon fabric and/or carbon fibers, the photoinitiator comprises a combination of phosphine oxide and phenyl-p-octyloxylphenyl-iodonium hexafluorantimonate, the thermal initiator comprises methyl ethyl ketone peroxide, the radiation comprises UV-A, and wherein the composition further comprises cycloaliphatic diepoxide and wherein curing of the composition is performed in the absence of heat from an external thermal source. 
     
     
       2. The method of  claim 1 , wherein the radiation source is turned off before complete curing of the composition is achieved and wherein curing of the composition is performed in the absence of heat generated by an external thermal source. 
     
     
       3. An article produced by the method of  claim 1 . 
     
     
       4. A method of curing a dual cure composition on at least one surface of a reinforcing core material comprising the steps of: (i) providing a dual cure composition comprising: at least one filler; at least one curable monomer comprising at least one of an ethylenic unit or cyclic ether unit or mixture thereof; at least one photoinitiator; and at least one thermal initiator; (ii) applying the composition onto at least one surface of the reinforcing core material; (iii) exposing the composition to radiation of a wavelength from a radiation source for a time to at least partially photocure the composition and to provide an exotherm sufficient to continue curing of the composition by thermal curing upon terminating exposure of the composition to the radiation to form a cured composition wherein the reinforcing core material is comprised of foam, slitted foam, honeycomb, or combinations thereof, and/or wood having resin filled pathways through the wood that enable transfer of heat to propagate through the wood and the composition to cure the composition, wherein the radiation source is turned off before complete curing of the composition is achieved and wherein curing of the composition is performed in the absence of heat generated by an external thermal source. 
     
     
       5. An article produced by the method of  claim 4 . 
     
     
       6. The method of  claim 4  wherein the reinforcing core material is comprised of foam, slitted foam, honeycomb, or combinations thereof. 
     
     
       7. The method of  claim 1 , wherein the radiation wavelength is in the range of from about 200 nanometers to about 1000 nanometers. 
     
     
       8. The method of  claim 4 , wherein the exposing occurs for a time period of about 1 second to about 5 hours. 
     
     
       9. The method of  claim 4 , wherein the composition is fully cured. 
     
     
       10. A method of curing a dual cure composition comprising the steps of: (i) providing a dual cure composition comprising: at least one filler; at least one curable monomer comprising at least one of an ethylenic unit or cyclic ether unit or mixture thereof; at least one photoinitiator; and at least one thermal initiator; (ii) exposing the composition to radiation of a wavelength from a radiation source for a time to at least partially photocure the composition and to provide an exotherm sufficient to continue curing of the composition by thermal curing upon terminating exposure of the composition to the radiation to form a cured composition wherein the photoinitiator comprises a combination of phenyl-p-octyloxylphenyl-iodonium hexafluorantimonate and any one or more of phosphine oxide and cycloaliphatic diepoxide. 
     
     
       11. The method of  claim 4 , wherein the photoinitiator comprises phosphine oxide, the thermal initiator comprises methyl ethyl ketone peroxide, and the radiation comprises UV-A. 
     
     
       12. The method of  claim 4 , wherein the photoinitiator comprises a combination of phenyl-p-octyloxylphenyl-iodonium hexafluorantimonate and any one or more of phosphine oxide and cycloaliphatic diepoxide and the radiation comprises UV-A. 
     
     
       13. The method of  claim 11 , wherein the cured composition has a thickness greater than 6 millimeters. 
     
     
       14. The method of  claim 11 , wherein the cured composition has a thickness from 2.5 millimeters to 16 millimeters. 
     
     
       15. The method of  claim 11 , wherein the cured composition has a thickness from 2.5 millimeters to 6.35 millimeters. 
     
     
       16. An article produced by the method of  claim 12 . 
     
     
       17. The method of  claim 10  wherein the filler is a UV opaque filler comprising carbon fibers, carbon black, carbon nanotubes, silicon carbide, boron nitride, titanium dioxide, zirconium oxide, chalk, calcium sulfate, barium sulfate, calcium carbonate, silicates, talc, mica, kaolin, silica, aluminum hydroxide, magnesium hydroxide, polymer powder, polymer fiber, or combinations thereof; wherein the cured composition has a thickness of at least about 0.1 millimeter. 
     
     
       18. The method of  claim 10  wherein curing of the composition is performed in the absence of heat from an external thermal source. 
     
     
       19. The method of  claim 10 , wherein the radiation wavelength is in the range of from about 200 nanometers to about 1000 nanometers. 
     
     
       20. The method of  claim 10 , wherein the exposing occurs for a time period of about 1 second to about 5 hours. 
     
     
       21. The method of  claim 10 , wherein the composition is fully cured. 
     
     
       22. An article produced by the method of  claim 10 . 
     
     
       23. An article produced by the method of  claim 18 .